OAK-8910 Improve OAK Lucene Index Documentation

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1884541 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/oak-doc/src/site/markdown/query/lucene.md b/oak-doc/src/site/markdown/query/lucene.md
index 03ff1c3..ab4e5b7 100644
--- a/oak-doc/src/site/markdown/query/lucene.md
+++ b/oak-doc/src/site/markdown/query/lucene.md
@@ -427,10 +427,11 @@
   would cause indexing to fail.
 
 type
-: JCR Property type. Can be one of `Date`, `Boolean`, `Double` , `String` or `Long`. Mostly
-  inferred from the indexed value. However in some cases where same property
+: JCR Property type. Can be one of `Date`, `Boolean`, `Double` , `String`, `Long`, or `Binary`. 
+  Mostly inferred from the indexed value. However in some cases where same property
   type is not used consistently across various nodes then it would recommended
-   to specify the type explicitly.
+  to specify the type explicitly.
+  A binary is only indexed if there is an associated property `jcr:mimeType`.
 
 propertyIndex
 : Whether the index for this property is used for equality conditions, ordering,
@@ -1049,7 +1050,7 @@
 
 #### <a name="mime-type-usage"></a>Mime type usage
 
-A binary would only be index if there is an associated property `jcr:mimeType` defined
+A binary is only indexed if there is an associated property `jcr:mimeType` defined
 and that is supported by Tika. By default indexer uses [TypeDetector][OAK-2895]
 instead of default `DefaultDetector` which relies on the `jcr:mimeType` to pick up the
 right parser.